Illuminating device



June 26, 1934.

R. E. BARCLAY ILLUMINATING DEVICE Filed June 1, 1931 Patented June 26, 1934 UNITED STATES ILLUMINATING DEVICE Robert E. Barclay,

Chicago, 111., assignor to Federal Electric Company, Chicago, 11L, a corporation of New York Application June- 1, 1931, Serial No. 541,391

11 Claims. (Cl. 178-122) My invention relates in general to the art of creating an electron flow through an ionized gaseous path.

One of the phenomena or results accomplished by an electron fiow through an ionized path is that the gaseous material forming the path is caused to glow and radiate light having color characteristics depending upon the gaseous material in which the electron flow occurs and my invention has more particular reference to a luminous element or lamp of novel construction for use in illumination, the novel features of which provide increased utility and moreover promote economy in the production of electrical discharge illumination.

Among the important objects of my invention is to provide a lamp unit of the class described wherein the cross-sectional area of the discharge path is reduced with the result that the power required to operate the device is reduced while the total amount of light emitted is increased.

Another important object is to provide a lamp of the class described having integral or built-in mirror means within the lamp whereby the illumination created therein will be reflected in all directions to thus increase the amount of illumination emitted by the device.

Another important object of the invention is to provide a device of the class described comprising an elongated tubular member having partition means dividing the member into a plurality of adjacently extending channels in which the illumination is created. Another important object is to provide a device of the class described comprising an envelope defining an outer zone in which illumination may be created and an inner zone, the walls of which may be silvered or otherwise treated to provide mirror means for reflecting the illumination outwardly.

Another important object is to provide a device of the class described comprising an en-- velope defining an electrical discharge channel, said envelope being silvered along one side to reflect the illumination created by the discharge.

Another important object is to provide a novel tubular element adapted for use in electric illumination.

Among the other numerous objects and advantages of my present invention is to provide the refinements including the construction of the base and terminal means carried thereby to provide a commercial unit which can be readily mounted in standard support fittings to facilitate the erection of the device in operative position.

Numerous other objects and advantages of the invention will be apparent as the same is more fully understood from the following description, which taken in connection with the accompanying drawing discloses a preferred em- 00 bodiment of the invention.

Referring to the drawing:

Figure 1 is a perspective view of a preferably glass partitioned tube which may be used in forming the envelope defining discharge are 05 tpaths in a device embodying my present inven- Figure 2 is a vertical section taken substantially along the line 2-2 in Figure 3, and, Figure 3 is a horizontal section taken substantially along the line 33 in Figure 2, both figures illustrating an illuminating device made in part from the tubular element shown in Figure 1 and embodying my present invention; and

Figure 4 is a vertical section taken substantially along the line 4-4 in Figure 3 to illustrate a modified construction embodying my present invention.

To illustrate my invention, I have shown on the drawing an electrical arc illuminating element 11 9 comprising an envelope 13 of transparent or translucent material, preferably glass, defining preferably sealed channels 15 adapted to contain a suitable, preferably gaseous, medium, which is capable of being excited and caused to glow by electrical discharge in the channels. These channels are or may be arranged circumferentially in the envelope, preferably around a central bore 17, the channels and central bore'being defined by partition means 19. Of course, the channels 15 need not necessarily be separated and it is within the scope of my invention to form these charmels as a single annular channel extending within the outer wall 21 of the envelope and encircling the wall defining the central channel. Iprefer, however, to form the envelope in such a way that the several channels 15 are separated the one from the other each extending longitudinally in the envelope.

In the device illustrated in Figure 1, the oppo- 10 site ends of each channel 15 are sealed in a manner well known in the art of glass blowing in order to close the channel and an electrode 23, of any suitable or well-known construction, is assembled in each end of each channel. The sev- 5 eral sealed channels 15 also are evacuated, bombarded, that is to say, subjected to high voltage and high frequency discharge arcs, the channel being subjected to low pressure in order to remove impurities which might efiect the operation of 11.

the device, and then filled with a suitable gas such as neon, argon, mercury vapor, or any other known gas capable of ionization and of sustaining electrical discharges. The several channels 15 may be thus filled each with the same gas or different gases may be introduced into the several channels for their several color effects, it being wellknown the various gases glow with and emit different color characteristics when subjected to an electron fiow along an ionized path therein.

The walls defining the central channel 1'7 also are or may be treated to provide a mirror surface, the inner walls being preferably coated with a film of quick silver, which may be applied by a flashing process well known in the art. The walls 19 defining the central channel also are preferably formed to create parabolic mirrored surfaces behind each of the channels 15. The creation of mirrored surfaces behind the channels 15 results in the reflection outwardly of any discharge created in the channel in front of the mirrored surface and, by forming the mirrored surfaces in parabolic form, a brilliant intensity of light reflection is obtained.

The upper and lower ends of the envelope 13 are preferably mounted in receptacles 25 comprising preferably molded cups in which the ends of the envelope are secured by means of insulating compound 2'7. The cups also are provided with terminal means 29 comprising, in the illustrated embodiment, prongs 31 in one end of the unit and co-operating sockets 33 in the other. These prongs are connected electrically with the electrodes 23 in the discharge channels by means of suitable conductors extending through the sealed ends. The terminals 31 at one end of the element also are adapted to co-operate with the terminals in the other-end so that a plurality of the devices may be connected together for series operation.

The terminals 31 also are or may be formed to co-operate with the terminals of a standard outlet socket whereby .the device is formed for detachable connection in a power circuit.

In Figure 3 of the drawing, in dotted lines at 35, is indicated a direct connection at the upper end of the element between the electrodes 23 of adjacent channels 15 so that the power for creating discharges in said channels may be applied solely at the base of the element. In such a device, of course, the upper terminals 33 may be omitted.

As shown in Figure 4 of the drawing, the electrodes at the upper ends of the channel 15 and the upper ends of adjacent channels 15 are placed in direct communication with each other by means of the dome-shaped connection 37 so that two adjacent channels 15 together with the space defined by the dome-shaped connection form an inverted U-shaped discharge path substantially as set forth in my co-pending application, Serial Number 541,390, filed the first day of June, 1931. In this construction also as in the construction indicated in Figure 3 of the drawing, the device may be operated through detachable connections made entirely at the lower end and may form an electric candle substantially as set forth in my co-pending application aforesaid. The device may be supplied with means providing for low voltage operation such as the transformer indicated at 39 in Figure 4, whereby a relatively low voltage applied between the terminals may be increased to a sufiicient degree to initiate and sustain an electron flow between the terminals 23 through the channel portions 15.

As aforesaid, an important feature of my present invention resides in the provision of an envelope defining a discharge channel and having a mirror surface whereby to intensify the illumination produced by the electron discharge and more particularly the arrangement of the mirror surface in parabolic form and also the provision of a central mirror surface surrounded by discharge paths whereby the illumination may be reflected in a plurality of directions and in fact in every direction radially of the unit. This feature coupled with the fact that the cross-sectional areas through which the electrical discharges occur comprises only a fraction of the entire area enclosed by the outer wall 21 of the envelope 13, provides a highly economical and efiicient product. Since the power required to drive the electron discharge through the fractional area, defined within the envelope 'by the paths 15, is considerably less than that which would be required to produce a discharge filling the entire bore of the encircling wall 21 of the envelope, while the effective illumination produced by the device illustrated is augmented by the mirror construction, the device of my present invention has manifest advantages.

The tubular member, forming the envelope 13, also is of novel construction and arrangement and has general utility in the field of illumination and one of the features of my invention resides in employing such an element per se in advancing the art of illumination by electronic discharge.

It is thought that the invention and numerous of its attendant advantages will be understood from the foregoing description and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts without departing from the spirit or scope of my invention or sacrificing any of its attendant advantages; the form herein before described comprising preferred embodiments for the purpose of illustrating the scope of my invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is as follows:

1. An elongated envelope of light-transmitting material comprising an outer wall and longitudinally extending partition means forming three or more separate channels extending within the envelope, at least one of said channels being surrounded inthe envelope by the other channels.

2. An elongated envelope of light-transmitting material comprising an outer wall and longitudinally extending partition means forming three or more separate channels extending within the envelope, at least one'of said channels being surrounded in the envelope by the other channels and a mirror surface formed in the walls defining said surrounded channel.

3. An elongated envelope of light-transmitting material comprising an outer wall and longitudi- 'nally extending partition means forming four or more separate channels extending within the envelope, at least one of said channels being surrounded by at least three other channels and having wall portions common to each of the surrounding channels, said common wall portions having a parabolic cross-sectional configuration.

4. An elongated envelope of light-transmitting material comprising an outer wall and longitudinally extending partition means forming four or more separate channels extending within the envelope, at least one of said channels being surrounded by' at least three other channels and having wall portions common to each of the surrounding channels, said common wall portions being curved inwardly at their mid-portions so that the inner walls of the surrounding channels will have concave surfaces.

5. An elongated envelope, of light-transmitting material, comprising an outer wall and longitudinally extending partition means forming four or more separate channels extending within the envelope, at least one of said channels being surrounded by at least three other channels and having wall portions common to each of the surrounding channels, said common wall portions having a parabolic cross-sectional configuration, and mirror means on said common wall portions.

6. An illuminating device comprising an elongated envelope of light-transmitting material comprising an outer wall and longitudinally extending partition means forming at least three separate channels extending within the envelope, at least one of said channels being surrounded in the envelope by the other channels, said surrounded channels containing a medium adapted to be excited to provide a light source within said surrounding channels, outwardly facing mirror means within said surrounding channels, and means associated with said surrounding channels for exciting the medium therein.

'7. An illuminating device comprising means defining a plurality of channels extending parallel and adjacent each other and including a central channel enclosed by the remaining chan nels and means forming a reflecting surface on the walls defining said channel.

8. An illuminating device comprising an integral translucent envelope having a plurality of parallel and adjacent channels extending therein, means associated with said channels to generate light therein, said envelope having an interior wall and means forming a mirror on said wall in position to reflect outwardly the light created in said channels.

9. An illuminating device comprising an integral translucent envelope having a plurality of parallel and adjacent channels extending therein, means connecting the ends of a pair of said channels together, additional means connecting the ends of another pair of said channels and means associated with said channels for generating light in said channels when electrically excited.

10. An illuminating device comprising an integral translucent envelope having a plurality of sealed channels extending in parallel adjacent relationship, a pair of said channels being connected together at one end of the envelope, and means to create electrical discharges in said connected channels and in another channel of the envelope.

11. An illuminating device comprising an integral translucent envelope having a plurality of sealed channels containing a gaseous medium adapted to glow when electrically excited, said channels being separated by an integral part of the envelope forming partition means separating the several channels, one of said channels being substantially U-shaped and separate means associated with each channel for exciting the gas therein.

ROBERT E. BARCLAY. 

